Luminescence studies on swift heavy ion irradiated nanocrystalline aluminum oxide

Pellets of nanocrystalline aluminum oxide synthesized by a combustion technique are irradiated with 120 MeV Au9+ ions for fluence in the range 5×1011–1×1013 ions cm−2. Two photoluminescence (PL) emissions, a prominent one with peak at ∼525 nm and a shoulder at ∼465 nm are observed in heat treated and Au9+ ion irradiated aluminum oxide. The 525 nm emission is attributed to F22+-centers. The PL intensity at 525 nm is found to increase with increase in ion fluence up to 1×1012 ions cm−2 and decreases beyond this fluence. Thermoluminescence (TL) of heat-treated and swift heavy ion (SHI) irradiated aluminum oxide gives a strong and broad TL glow with peak at ∼610 K along with a weak shoulder at 500 K. The TL intensity is found to increase with Au9+ ion fluence up to 1×1013 ions cm−2 and decreases beyond this fluence.